Pius XII, who was pope from 1939 until his death in 1958, will now be eligible for beatification once a miracle attributed to him has been recognised. Photograph: Corbis

Jewish leaders from around the world expressed their outrage today after the Pope opened the way for his controversial wartime predecessor to be made a saint, with some calling the possible beatification of Pius XII as "inopportune and premature".

Benedict signed a decree last Saturday on the virtues of Pius, who has been criticised for not doing enough to stop the Holocaust. The decree means he can be beatified once a miracle attributed to him has been recognised.

Beatification is the first major step towards sainthood. But Benedict, who has long admired Pius, continues to draw fire for ignoring concerns over the controversial pontiff.

Among those to criticise him was the World Jewish Congress, whose president, Ronald Lauder, said: "As long as the archives about the crucial period 1939 to 1945 remain closed, and until a consensus on his actions ‑ or inaction ‑ concerning the persecution of millions of Jews in the Holocaust is established, a beatification is inopportune and premature.

"While it is entirely a matter for the Catholic church to decide on whom religious honours are bestowed, there are strong concerns about Pius XII's political role during world war two which should not be ignored."

He called on the Vatican to immediately open the files on the controversial figure. "Given the importance of good relations between Catholics and the Jews, and following the difficult events of the past year, it would be appreciated if the Vatican showed more sensitivity on this matter," he added, referring to Benedict's rehabilitation of a Holocaust-denying cleric, Richard Williamson.

The incident sparked worldwide condemnation from prominent Jewish groups and individuals and placed an additional strain on interfaith relations, which were already under pressure after the pope issued an edict permitting a prayer that called for the conversion of Jews.

In France, the country's chief rabbi urged the Vatican to abandon its mission to beatify Pius. Gilles Bernheim said: "Given Pius XII's silence during and after the Shoah [Holocaust], I don't want to believe that Catholics see in Pius XII an example of morality for humankind. I hope that the church will renounce this beatification plan and will thus honour its message and its values."

The renewed source of tension could cast a cloud over Benedict's inaugural visit to Rome's synagogue next month.

Giuseppe Laras, president of the Assembly of Italian Rabbis, told the Italian daily newspaper La Repubblica: "I hope it goes ahead but after this latest move I wouldn't be surprised if it is cancelled. While I respect the autonomy of the church in matters of sainthood, I don't see how the pope could have taken such an untimely decision. Anything can happen now."

The Vatican argues that Pius worked quietly behind the scenes because direct interventions might have worsened the situation for Jews and Catholics in Europe. It is a position many Jews have rejected.

Yesterday Benedict, in a look back at an eventful year, recalled his trip to Jerusalem and described his visit to the Holocaust memorial as "an upsetting encounter".